21542024 has 32 divisors (see below), whose sum is σ = 47654400. Its totient is φ = 8933760.

The previous prime is 21541979. The next prime is 21542063. The reversal of 21542024 is 42024512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21541987 and 21542005.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4469 + ... + 7940.

It is an arithmetic number, because the mean of its divisors is an integer number (1489200).

Almost surely, 2^21542024 is an apocalyptic number.

It is an amenable number.

21542024 is an abundant number, since it is smaller than the sum of its proper divisors (26112376).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21542024 is a wasteful number, since it uses less digits than its factorization.

21542024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12453 (or 12449 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 21542024 is about 4641.3386000162. The cubic root of 21542024 is about 278.2459393908.

Adding to 21542024 its reverse (42024512), we get a palindrome (63566536).

The spelling of 21542024 in words is "twenty-one million, five hundred forty-two thousand, twenty-four".